Improvement in machines for grinding hand-saw blades



i l I, `.DAvrDmlvL Marroni), of Norwalk, in the countyof Huron and State of Ohio, have invented certain Improvements in Machines for Grinding Hand-Saws, of. which `the following isa specification. r The nature andobject ct' my invention consist in such position that ,the part'of the blade from which a `the greatest amount of steel'.` is to be `removed will traverse the whole grinding-suriace.

this specification-.-` a a Figure 1 is a vertical longitudinal s chine embodying my invention, l Figure 2 is a plan Vo `top.`v. A is the frame of the machine, which should be substantiallyconstructed, to resist the vibration of the operatingparts. 4 4 l`4 C B and O lare shafts, attached "to the frame. of machine by suitable boxes, in which they turn, and `are isupported-by their respective steps b and c, the latter of which isadjnstable by means of screws m in.

f The metallic table K and the grindstone or other suitable grinding-wheel H, having groove L,- are i firmly secured to their respective shafts O and `B by means of clamps andfnuts.` Motion is imparted to shaft B by a belt, lact-ing on driving-pulley `D,Hand is communicated toshait f the same, viewed from the O lbeing regulated by the dii'erence in the' sizes of It is convenient to have the saw-plates-J J` J J parallelograms in form 'en their yfaces', and they should 'be oi' suicientthckhess to prevent springing under the pressure necessary to secure rapid grinding. i W Y `Their length and `breadthshonld `be sucient to receive on their faces the-saw-blades I I II,- and vthey'may he fastenedxto the table by bolts or screws,

with their heads conntersunk `into and level with 'the a `face ofthe plate. a

` l The plates are furnished'with adjustable dogs N N N N, which are tted to and slide'snugly iridovet tail-grooves, cut int-o and across theface of the plates.

The dogs shouldbe made' of steel, with sharp y edgesprojectug `toward .the center of the plate, and rising above its facel highlenough so that, when the edges are pressed againstthe face'and back of vthe bladefthey gripe it tightly and hold it firmly. while 4it is beinggronnd.l

The saw-bladesshouldrest on the plate-with their faces inward toward the axis of table K. 4 Haudfsaws-should be ground on a bevel from face to back, the back being the thinner.

The Schedule referred to inzthese Letters Patent and making part, ofthe saine.

` presenting hand-saw blades to a grinding-surface in In the-accompanying drawingmakinga` part -ot ection of a mal C by belt G, the relative motionf of the shafts B andV l pulleys E andFfshaitBhaving the higher motion.`

f dhtiied (t-airs @nicht @tithe4 'DAvrD.MMnFroRn orfNoRWALu-omc "LettersPatent No. 106,071, dc'tedAhguslt 2, 1870.

IMPRovEMnNT IN 1 vraizznr1infzs r-oizl @BINDING HAND-SAWBLADS- This result is seoured'byraising theouterredge of the plate J a' distance sucient to'place the plate on an'angle with thetable K, correspondingwith the bevel desired on the saw-blades.

When the plate is raised on theabove-described angle with the table, and the sawblade is placed `on it, face inward, as directed, also on a line parallel with'the inner 'edge-of the plate, it will be ground on the desired bevel from face to back, and the-face an even and regular thickness from heel to point;

bntif it is desired tofsecure the' beveland, at the .same tiine,give the 'face of the saw a regular taper fro'mheel to point, leave the plate'in the position de-V 'scribed above, the face of 'thesaw inward, as before,

but 'place the back of the blade on` a line parallel with the outer edge of the plate, 0r any approxima- 'tion ofthev blade from its former torthe latter posi;

tion'will taper the saw, when ground, in exact proportion as'it approaches Athe latter position.

The groove lIl, or its"eqn`ivalent, -which is any means ot' removing or wearing away the grinding- ,surface Aof stone or grinding-wheel H, is necessary in order to prevent the mere point of the heel, at

Thesaw-blades being'n position on the saw-plates," as above described, the griudstone IEI andtable Kare y rotated by belts, as above'described, in the direction indicated by the arrowsin iig. 2.

, The table K 'is elevated by screws m in, or any other suitable device, untilthehighest pointof each blade is reached by the grinding-snrf'ace.v

As the backs ofthe' saws are elevated to give the proper` bevel, they comein contact with the grindingsurface first, and as the steel from near the backs oi' the blades is removed, the lower parts of. the blades are reached and ground,nntil the sides of the faces of the saws are finally reached and trued up.'

The blades are then turned over, and their plates elevated sufficiently. to give to the second. side ot' the blades thesame'bevel as was-given to the rst.

v I am aware that a disk or table, rotating with its axis parallel with and eccentric to the axis of a rctating grinding-surface, has been long known and used. This Ido not claim; but

What I claim, and desire to secure by Letters Patent, is- 4 1. The means hereinhefore described, for pressing dogs N, when said plates are arranged to or placed upon a proper angle to give the be set at necessary bevel to the blade, substantially as described;

.DAVID M. MEF

Witnesses: SUSAN PEEBLES, F. A. WILDMAN.

FORD. 

